Liposome - DNA is wrapped in lipid olecules. These are fat-soluble and can cross the lipid bilayer by diffusion

Ti Plasmids - inserted int Agrobacterium tumefaciens. Plants can be infected and the DNA is inserted into the plant's genome

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Genetic Engineering Process

DNA fragment isolated using restriction enzymes

DNA frgmetns inserted to a vector (plasmid/bactriophages) - Vector DNA cut using same restriction enzymes so the sticky ends are complementary to DNA fragment. Vector DNA and Fragment mixed with ligase which seal the sugar-phosphate backbone to form recombinant DNA

The vector transfers the gene into bacteria

If a plasmid is used, the plasmids are added to the cell in ice cold CaCl2 solution so the cell walls are more permeable. The mix is then heat shocked which encourages the cells to take up the plasmid

With a Bacteriophage vector, the bacteria is infected when the bacteriophage injects its DNA which integrates into the bacterial DNA

Cells that take up the vectors are transformed

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Identifying the transformed Bacteria

Identify the tranformed bacteria with marker genes, which are niesrted with the desired gene into the vector - only transformed bacteria contains the marker gene

Marker gene can be antibacterial resistance so that when bacteria are grown on an antibacterial agar plate, only cells with the marker gene survive and grow

Marker gene can be for fluorescene - when the agar plate is under UV light, only transformed cels fluorese.